Technical Field
The present invention relates to rotary fluid machinery equipment, in particular to equipment capable of being used for synchronous rotation of a rotor and a cylinder body in the equipment such as a compressor, a fluid pump, a vacuum pump, a multiphase mixed transportation pump and the like, and specifically relates to an externally-supported rotary fluid machinery and a method for eliminating axial rotor displacement.
Related Art
At present, the rotary fluid machinery represented by a rotary compressor is very popular due to its small structural size, small wear, stable operation and low noise, for example, Chinese Patent ZL2008100067148 is a rotary compressor with a relatively ideal structure. Such compressor has the characteristic that an air cylinder and a rotor consist of two cylinders, a relative movement speed between which is very small, the air cylinder 2 is supported in a box body 1 through a bearing 16 so as to ensure flexible rotation of the cylinder 2, as shown in FIG. 1, due to communication with an air inlet cavity, the bearing is extremely easily polluted by a medium to affect the service life, due to the difficulty in sealing between the bearing and high temperature high pressure gas in an air outlet, the bearing is extremely easily affected by a high temperature high pressure fluid at an exhaust port to reduce the service life, a damage to the bearing is lethal for the rotary compressor, but there is no good solution at present, and the normal and long term operation of such equipment is severely influenced.
In addition, in the rotary compressor, since the rotor is subjected to the action of the pressure of a discharged medium (gas or liquid), the rotor is subjected to certain axial displacement, such that a distance between the end surface of the rotor and the end surface of the inner wall of the air cylinder is reduced, collision occurs or wear is aggravated under severe conditions, a traditional processing method is to increase a high pressure cavity at one end of the rotor, a high pressure introduced from a high pressure cavity is used to balance a thrust force, and such structure has the first problem that the complexity of the structure is increased and the second problem that since the attenuation of the introduced pressure is larger, a lethal effect is very easily caused after the efficacy is lost, in order to prevent such accidents, the current method is to increase a set of monitoring mechanism that prevents the aggravation of the wear due to overlarge axial movement, when a gap is smaller than a set value, the system is automatically cut off and halted and alarms, which greatly increases the manufacture cost and reliability, and there is no better solution for this problem yet.